Coupling devices for mechanically and hydraulically coupling a fuel injector to a fuel rail are in widespread use, in particular for internal combustion engines. Fuel can be supplied from a fuel tank to an internal combustion engine by the fuel rail and the fuel injector.
In order to keep pressure fluctuations during the operation of the internal combustion engine at a very low level, internal combustion engines are supplied with a fuel accumulator to which the fuel injectors are connected and which has a relatively large volume. Such a fuel accumulator is often referred to as a common rail.
Known fuel rails comprise a hollow body with recesses in form of fuel injector cups, wherein the fuel injectors are arranged. The fuel injectors can be coupled to fuel injector cups in different manners. The coupling of the fuel injectors to the fuel injector cups that supply the fuel needs to be very precise to get a correct injection angle.